T2: Quantum matter with anisotropic dipole-dipole interaction

In this project, we study ground state properties of atoms with strong magnetic moments and polar molecules. The main focus is on setups, which are in close connection to the experimental groups within this collaborative research project, and appear as a consequence of the anisotropic dipole-dipole interaction. One important aspect of the dipolar interaction is that it provides a natural mechanism to couple internal spin/rotational levels to orbital angular momentum. This spin-orbit coupling is at the heart of demagnetization cooling for atomic gases with large magnetic moments. We will explore the potential to exploit the analog of demagnetization cooling in polar molecules in order to cool polar molecules below quantum degeneracy, and therefore will develop a protocol for demagnetization cooling of polar molecules. Strong spin-orbit coupling is a driving mechanism for topological states for matter. Therefore, we study the possibility to realize topological band structures for atoms with large magnetic moments as well as for polar molecules. A careful analysis will be taken to identify a minimal setup and clear experimental signatures of such topological bands. A third aspect is the full understanding of phase separation in a multi component system with dipole-dipole interaction. Such a multi component setup is naturally realized with Dysprosium atoms. Finally, the stabilization of polar molecules with strong dipole moments is most conveniently achieved in a two-dimensional layered setup. Within this regime, we expect that the experiments will first explore the parameter range, where the molecules are dominated by dipolar interactions with only weak influences of the quantum fluctuations. We will analyse the classical arrangement of polar molecules in a multi-layer setup and study the crossover into the quantum regime